Which tool is frequently used for vulnerability assessment by mapping hosts and services on a network?

• A. nmap
• B. ncat
• C. netcat
• D. wireshark

Answer: (A)

Identifying which devices exist on a network and what services they expose is a fundamental step in vulnerability assessment. Nmap is built for this purpose: it can discover hosts through various scanning techniques, determine which ports are open, and identify the services and often their versions running on those ports. This gives you a map of reachable machines and exposed software, which is essential for spotting vulnerabilities like outdated versions or misconfigurations.

Nmap’s power also comes from its service/version detection and the Nmap Scripting Engine, which can run automated checks to flag known vulnerabilities or risky configurations, turning discovered details into actionable risk insights. That combination—who’s on the network, what’s open, and what versions are running—directly supports assessing security posture.

The other tools serve different roles. General-purpose connection tools are handy for manual testing and data transfer but aren’t designed to scale discovery and detailed service enumeration across a network. A packet analyzer focuses on inspecting traffic to help troubleshoot or study network behavior, not on mapping every host and service to assess vulnerabilities.

So, for vulnerability assessment that involves mapping hosts and services, the best choice is Nmap.